.overlay{background:#000;cursor:pointer;display:block;position:fixed;top:0;left:0;width:100%;height:100%;z-index:900;opacity:0;}

.modal{display:none;background:#404040;z-index:910;padding:5px;position:absolute;-webkit-border-radius:2px;-moz-border-radius:2px;border-radius:2px;top:-999px;}
.modal >div{background:#fff;padding:30px;width:400px;}